Same problem here, with Yamaha rx-v679 which is not detected by Spotify connect. Everything is up to date, I tried with a laptop, with my phone, thorugh wifi or ethernet, I tried resetting my Yamaha, I tried the DHCP trick found on the forums... Nothing works, it's very frustrating.

Same issue on Pioneer SC-LX59 (and Fritz!Box 7490). Everything else works on the AVR and Spotify works on all other devices in the same network. Sometimes works for hours, sometimes Pauses every few seconds, apparently regardless of traffic.

Contacted Pioneer/Onkyo (German support) and all their suggestions did nothing.

Here the suggestions from German support (in German and pretty long, sorry), in case it helps anyone else:

Yep same thing happens to me on my Yamaha rx-a3070. Yamaha firmware is up to date and Spotify app is up to date. I get no error messages but Spotify connect stops randomly. This has been happening since May. Pretty much renders Spotify connect useless for me.

Also tried testing three of my family members phones. Spotify connect stops randomly on all.

Hey Spotify, can you try and fix this issue for the entire community that uses Spotify connect?

I have Spotify Connect on a Goodmans Heritage ii DAB radio but when I try to connect from iPhone it plays for a bit then stops and starts - all the while playing on my iPhone... anyone know anything about this?